The Japanese Navy’s 5 Most Lethal Weapons of War

July 5, 2015 Topic: Security Region: Asia Tags: JapanJapan's Navy

The Japanese Navy’s 5 Most Lethal Weapons of War

Tokyo brings the thunder on the water.

The modern Japan Maritime Self Defense Force trace its roots to the Imperial Japanese Navy. Established in July 1869, the Imperial Navy was one of the first formal institutions—military or otherwise—of a new, modern Japan.

The current-day Maritime Self Defense Forces (MSDF), created during the 1950s, is the result of lessons learned during World War II . The American blockade of the Home Islands led to widespread hunger and economic decline. Modern Japan is still heavily reliant on secure sea lanes, and the MSDF was geared heavily toward anti-submarine and anti-mine warfare. The end of the Cold War did little to change that.

The rise of the People’s Liberation Army Navy (PLAN) has prompted the MSDF to undertake long-overdue changes. In response, MSDF ships are becoming larger and more capable. The end result should be a Maritime Self Defense Force capable of defending against the PLAN  while assisting allies and protecting Japanese interests overseas. With that said, here are five of the MSDF’s most lethal weapons of war.

Hayabusa-class Patrol Craft:

Japan’s version of the littoral combat ship, the six fast patrol craft of the Hayabusa (Falcon) class are unique in the MSDF. Similar to the “ Streetfighter” littoral combat ships originally envisioned by the U.S. Navy, they are Japan’s only surface combatants under 2,500 tons, maxing out at 240 tons fully loaded. Pound for pound, the Hayabusas are the most lethal ships in the fleet.


The small size and agility of the Hayabusa class allows them to hide out among Japan’s many island chains and coastline, conducting hit and run missile attacks on much larger enemy ships. In wartime they could be assigned to the Ryukyus against China, or the southern Kurils against Russia.

Three General Electric GM500 gas turbines give the Hayabusas a top speed of 46 knots. Rather than traditional propellers, the scrappy little patrol boats are powered by three pump jet propulsion units, which provide increased maneuverability, improved shallow water performance, and a lower sonar signature.

Despite their size, the Hayabusa class is packed with offensive weaponry.  Forward of the bridge and mounted in a stealthy turret is a 76mm OTO Melara gun , common in Western navies and capable of engaging surface targets. The ships also carry four SSM-1B anti-ship missiles, the same as carried on the Atago class. Armament is rounded out by a pair of .50 caliber machine guns.

The main downside of the Hayabusas is their lack of defensive armament. Primary defensive systems are a pair of Mark 36 Super Rapid Bloom Offboard Countermeasures Chaff and Decoy Launching Systems. The Mark 36 is capable of launching chaff (to fool off radar-guided missiles) or infrared decoys (to throw off infra-red guided missiles). The 76mm gun can be used against aircraft and missiles but is not ideally suited to the task.

Atago-class Aegis Destroyer:

The Atago-class destroyers are some of the most capable surface warships in the world. Modeled after the American Flight IIA Arleigh Burke destroyers, the Atago class is capable of a little bit of everything, from engaging targets in near space to anti-submarine warfare, and capable of doing it all extremely well.

The most important part of the Atago class is the combination of the SPY-1D Aegis radar system with SM-2 surface to air missiles. The Aegis combat system is capable of detecting aerial threats out to 100 miles, from cruise missiles to high-flying aircraft, and dealing with massed attacks of both. This makes, the Atagos, like the American Ticonderoga-class cruisers and Arleigh Burke-class destroyers, the prime air defense asset of any naval task force.

Unlike the previous Kongo class, the Atago class lacks a ballistic missile defense capability. As both China and North Korea make advances in ballistic missiles, Japan has decided to upgrade both ships to help take part in the BMD role. A contract for $124 million in Aegis upgrades to both Atago and Ashigara was awarded to Lockheed Martin on May 27th.

The Atago class features one Mark 45 5-inch naval gun, the same used on American surface ships, housed in a stealthy turret. The gun is capable of engaging surface targets, providing naval gunfire support, and engaging aircraft and missiles. Further gun armament is provided in the form of two Phalanx CIWS close-in weapon systems.

The Atago class can also hunt and destroy enemy submarines with its hull-mounted AN/SQQ-89 undersea warfare combat system, which combines an active/passive sonar system with ASROC rocket-propelled torpedoes. The system can also input and combine data from embarked SH-60J/K helicopters, which the Atago class typically carries at least one. Like American surface ships, the destroyers are also equipped with two triple 324-millimeter anti-submarine torpedo mounts for close-range work.

Finally, the class is fitted with eight SSM-1B anti-ship missiles. Similar to the American Harpoon, the SSM-1B has a internal navigation system/active radar seeker system and can strike targets at ranges of up to 180 kilometers. The missile packs a 255 kilogram high explosive warhead.